Naturally the 6800 Ultra is the more desirable card however they are hard to come by and so the prices are pretty high but the 6800 GT is still common enough to be had on the cheap should one take the time and shop around.

I would actually suggest against going for the 6800 Ultra. The difference between the two cards is just 50MHz on the core and memory and the 6800GT already has more than enough memory bandwidth AFAIR, so that's pretty moot. You can always increase the core if not by 50 MHz, then certainly by 25MHz.

The 6800 Ultra requires quite a bit more power, seeing as it actually has two 4pin molex connectors instead of 1, which is why I would avoid it. I had one, it died and I never really looked back. 6800GT all the way.

I have good experiences with both and even LE version. By your logic if there is only 50MHz between them and Ultra requires 2 molex connectors then GT would be underpowered when overclocked to Ultras specs.

GeForce 6800LE/6800 AGP - 1.2 volt GPU, 325mhz.
GeForce 6800GT AGP - 1.3 volt GPU, VRM is missing some components, 350mhz.
GeForce 6800Ultra AGP - 1.4 volt GPU, 400-425mhz.

All reference design cards can be softvoltmoded up to 1.5v. Some manufacturers made improved GT models with better memory (Gainward) and full VRM (ASUS),

I wouldn't pay a huge premium for an Ultra.
The AGP 6800GT and Ultra are built on the same card. The Ultra is just configured to reliably run the GPU and RAM harder than the GT does.

The Ultra populates a few more components in the onboard power supply (including the 2nd power connection) and has upgraded cooling - not sure if the fan is more powerful, or if it's just a heavier heatsink. It also has a different BIOS that clocks the card faster and I think raises operating voltages.
The GPUs are the same, but presumably the "Ultra" GPU is explicitly tested at the higher clock.
I'm not sure if the RAM is the same though - possibly the GT RAM would not be rated at the higher speed. When overclocking is considered, I doubt this would amount to much of an issue.

So by filling in missing components, improving the cooling, and flashing the BIOS, a 6800GT effectively becomes an Ultra. Unless you're unlucky and your GPU or RAM can't handle the Ultra clocks.

Old internet posts show that lots of people skipped the details and just flashed the BIOS. Apparently this worked well enough, but I have no idea how hot it would run with the stock "GT" heatsink.
You could probably just upgrade the heatsink and ignore the rest, and clock it close to Ultra levels. Especially if you can keep a lower GPU voltage than what the Ultra BIOS uses.

I'd upgrade the heatsink on the Ultra too. That card is noisy. The 5800U, 59x0U, and 6800U are all have quite annoying blower coolers.

You can use 7000 series on Win98 with moded drivers.
However going to 7900 GTX might be too much though (moded GPU driver doesn't like 512MB with some configurations).
7900 GT or 7800 GTX are your next best bet in that case.
Buy a 7800 GS(GT)/7900 GS(GT), if you need AGP slot.

6800 Ultra AGP owner here.
I got it for bragging rights. I have fond memories of Win98 era and AGP so I can say, yes, I have the best and final graphics card that officially supports Win98.

But nothing in Win98 really wants that much power, I doubt you'll notice any real world difference compared to a GT and if a game is upto pushing either card its modern enough to work in XP.

and as agent_x007 said as I was typing this, Later PCI express cards can be hacked to run with Win98 so really they aren't even the best card for WIi98 either.

easiest one to find though is a 6800GS AGP, all 6800GS AGP cards are NV40 12pp @ 325 with 1ghz ram, and they all unlock to 16pp/6VS as this was after the 6800GT/Ultra was discontinued and was just to get rid of dies prior to 7600GT thats your best bet

Good call, I didn't know 6800GS was NV40 based. There was also the 6800 XT, but I think it was impossible to enable the additional pipelines on this one, I forget if it was even NV40 based.

6800GS AGP, all 6800GS AGP cards are NV40

They don't.

The Serpent Rider wrote:

6800GS AGP, all 6800GS AGP cards are NV40

They don't.

They are, its the PCIe versions at are NV41 and NV42, unless you get some really late like 2007 6800GS end of life product, but the aGP verion runs at 325mhz instead of 425mhz just because the 130nm NV40 couldn't hit 425

The Serpent Rider wrote:

http://obrazki.elektroda.net/74_1232392155.jpg […]
Show full quote

What'ts your die?

That's 6800GS NV42 (sometimes NV41). And I am pretty sure that's one of the most common 6800GS AGP cards.

The Serpent Rider wrote:

That's 6800GS NV42 (sometimes NV41). And I am pretty sure that's one of the most common 6800GS AGP cards.

Never seen any NV42 AGP 6800GS cards, maybe its a Europe thing, but they had plenty of NV40 dies left over, and the HSI chip adds cost to a budget part that's not ideal

Thanks for all the info. I ended up buying a 7800GS 256 mb ram. I hope it wont be to hard to get that working in windows 98 with the unofficial drivers

vabis wrote:

Thanks for all the info. I ended up buying a 7800GS 256 mb ram. I hope it wont be to hard to get that working in windows 98 with the unofficial drivers

Good luck. For the record, nVidia is known for breaking compatibility with older games on each newer driver version, so don't be surprised if you run into issues (For this particular reason, many consider the nVidia Geforce 4 and FX (with period-correct drivers) to be the last 9x-friendly video cards). It should be fine for most XP-era games.

KCompRoom2000 wrote:

vabis wrote:

Thanks for all the info. I ended up buying a 7800GS 256 mb ram. I hope it wont be to hard to get that working in windows 98 with the unofficial drivers

Good luck. For the record, nVidia is known for breaking compatibility with older games on each newer driver version, so don't be surprised if you run into issues (For this particular reason, many consider the nVidia Geforce 4 and FX (with period-correct drivers) to be the last 9x-friendly video cards). It should be fine for most XP-era games.

Right, I will have both 98 and XP installed =)